Clustering of K-band selected local galaxies

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We present detailed clustering analysis of a large K-band selected local galaxy sample, which is constructed from the 2MASS and the SDSS and consists of 82,486 galaxies with 10 < K < 13.5 and 0.01 < z < 0.1. The two-point correlation function of the magnitude-limited sample in real space at small scales is well described by a power law ξ(r)=(r/6.44±0.23)⁻¹.⁸¹±⁰.⁰². The pairwise velocity dispersion is derived from the anisotropic two-point correlation function and find the dispersion σ₁₂=685± 17 if its scale invariance is assumed, which is larger than values measured in optical bands selected galaxy samples. We further investigate the dependence of the two-point correlation function and the σ₁₂ on the g-r color and the K-band luminosity, obtain similar results to previous works in optical bands. Comparing a mock galaxy sample with our real data indicates that the semi-analytical model can not mimic the σ₁₂ in observation albeit it can approximate the two-point correlation function within measurement uncertainties.